code: def define_graph(self):
      self.data = self.inputs()
      input_data = self.data
      data = input_data.gpu() if self.device == "gpu" else input_data
      out = self.pad(data)
      return input_data, out
  
imports: import numpy
  import nvidia.dali
  import nvidia.dali.fn
  import nvidia.dali.math
  import nvidia.dali.ops
  import nvidia.dali.types
  from nvidia.dali import Pipeline, pipeline_def
  from nvidia.dali.backend_impl import TensorListGPU
  from nose_utils import assert_raises
  from test_utils import RandomlyShapedDataIterator, generator_random_axes_for_3d_input, generator_random_data, as_array
label_desc: Use image node_id 2 for calling the PadSynthDataPipeline obj's underlying member method code with example usage: obj.define_graph() and returns: input_data,  out